1. Field of the Invention
The present invention relates to a spindle motor, and more particularly, to a shaft fixing type spindle motor in which a shaft is fixedly installed.
2. Description of the Related Art
A shaft fixing type spindle motor, in which a shaft having strong impact resistance is fixed to a hard disk driving device box, is generally mounted in an information recording and reproducing device such as a hard disk driving device for a server or the like.
That is, the shaft is fixedly installed in the spindle motor mounted in the hard disk driving device for a server in order to prevent information recorded in the server from being damaged and being unrecordable/unreadable due to an external impact.
As described above, when the fixed type shaft is installed, two sleeves, two fixed members, two covers for shielding upper and lower portions of the fixed members, and the like, are generally required in order to configure a fluid dynamic bearing assembly filled with lubricating fluid. In other words, a number of components are required in order to configure the fluid dynamic bearing assembly including the fixedly installed shaft. Since a number of components are required in order to configure the fluid dynamic bearing assembly as described above, manufacturing costs may increase.
Meanwhile, since it is demanded that a spindle motor used for an enterprise hard disk driving device has high reliability, maintaining an amount of lubricating fluid filling a fluid dynamic bearing assembly including a fixing type shaft is required.
That is, a lubricating fluid sealing technology capable of suppressing a reduction in an amount of lubricating fluid due to evaporation is in urgent demand.